For generic information about the wifi-connect service you have to consult wifi-connect/README.
The docker-compose files (especially docker-compose.yml) in this repository describe my specific setup.
Note that in my specific setup the captive portal cannot use port 80 as this is clashing with the traefik service that is also listening to that port. Therefore the captive portal is configured to listen to port 1000.
I have to execute following steps if I need to (re)configure the WiFi of my device:
wifi-connect...
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